Sellabration (sell + celebration)

A “sellabration” or “sell-a-bration” (sell + celebration) is an event that retailers often hold featuring discounted products. “Sell-abration” has been cited in print since at least 1923 and the term has frequently been used by car dealers.
 
Another term for a “sale celebration” is “saleabration.” Similar sales terms include “saleathon” and “sellathon.”
       
 
7 October 1923, The Times-Picayune (New Orleans, LA), pg. 2 ad:
Sell-abration Sales Begin Monday
(Feibleman’s—ed.)
 
30 June 1933, Indiana (PA) Evening Gazette, pg. 13, col. 1 ad:
We’re Staging a
SELL-A-BRATION for the 4th!
(Butler’s grocery—ed.)
 
13 April 1939, Manitowoc (WI) Herald-Times, pg. 13, col. 5 ad:
We make it a real SELLabration of the progress of the food industry with these outstanding values in Nationally Known Grocery Products.
(Leads grocery—ed.)
 
30 April 1939, Pampa (TX) News, pg. 1, col. 2:
“Sellabration” Opens
With Parade of Cars

Pampa’s Parade of Progress, a month of outstanding service by Pampa merchants, was ushered in yesterday with a parade. The unusual “Sellabration” will last through the month of May with a parade a week one of the features.
 
2 March 1941, San Francisco (CA) Chronicle, pg. A3, col. 5:
“Sellabration”
Chevrolet
Salemen
In Contest

Since the first of the year Chevrolet salesmen in the new and used truck departments of Oakland Zone dealers have been competing in a hot battle for honors in the “Jamboree Sellabration” event, according to George Green, truck zone manager, who this week announced that already 73 men have qualified for the big list of prizes.
 
Google News Archive
29 November 1953, The Spokesman-Review (Spokane, WA), pg. 14, col. 1 ad:
Greatest Used Car Sell-a-Bration of the Year
(Ford Stoddard-Wendle Motors—ed.)
 
Google Books
Amole One More Time
By Gene Amole
Boulder, CO: Johnson Books
1998
Pg. 17 (November 25, 1993):
But good old Thanksgiving Day remains on Thursday, like a rock. There are very few red-tag sales, doorbusters, sell-a-brations or inventory clearances on Thanksgiving Day.